Maintaining UPS/car batteries

[umans]

I need to buy a digital multimeter having AC & DC current measurement support.My purpose is to check UPS charging current, battery voltage, AC voltage and consumption of electrical appliances.Please guide me from where i can find this in Lahore, brand, model No and price as well...

[talhawaleed]

A good quality one should cost you somewhere from Rs 2000 to Rs 2500. Now there are many different models and brand available in market so whatever you buy, try to buy good quality equipment.

[Xulfiqar]

the wire isnt v thick,ive used 2 8 guage wires for it

that is pretty thick. But make sure that your negative circuit is equally heavy duty too. most jap cars have terrible grounding points and suffer from grounding problems. AND NO - this does not mean a high perf grounding kit is required.

Just simple wires with copper lugs and star washers that bite into metal.

[kaokabm]

I am having good experience with using only the battery water sold by the battery wala shop. not talking about the packed bottles. Just buy the open diluted water from any battery shop.

[umans]

i bought Phonix 50AH battery yesterday for my alto.i cant prepare disstilled water at home so i bout Pyro electrolight which claim that it is prepared using deionized water.The SG mentioned on bottle was 12.25 but meter showed 1190.After charging full night its open terminal voltage is 12.46 and SG in 1210.also electrolyte level has increased after charging.
now please guide me should i prepare higher gravity solution, drain some existing electrolyte and add the higher gravity salution to get 1250 SG
or
continue using battery and when fillup required, add electrolyte instead of distilled water
experts please guide me.....

[talhawaleed]

For car batteries, gravity up to 1250 is perfectly fine. Don’t do anything with the electrolyte and check the gravity after 15 days if you car is in constant use.
Even after 15 days you are not satisfied with the electrolyte gravity then you should have a solution of electrolyte ready of higher gravity ready which should be prepared with distilled water. You can then take the small quantity of existing out using hydrometer and pour the new electrolyte in order to compensate for week gravity.

[bilal_masood91]

Such and informative Thread,Hatts off for the Thread Owner.

[umans]

For car batteries, gravity up to 1250 is perfectly fine. Don’t do anything with the electrolyte and check the gravity after 15 days if you car is in constant use.
Even after 15 days you are not satisfied with the electrolyte gravity then you should have a solution of electrolyte ready of higher gravity ready which should be prepared with distilled water. You can then take the small quantity of existing out using hydrometer and pour the new electrolyte in order to compensate for week gravity.

thanx alot talha bhai...
now another problem is with UPS battery... it is 6 months old OSAKA IT 1500 (150AH) battery.At that time i prepaired the salution myself using Pyro deionized water according to ur instructions.previously it was giving about 3.50 hours backup on 370Watt load (250 watt cooler + 120 watt LCD).By the time backup is reduced and now its giving about 50minutes backup on 250 watt load....
current status of battery is
after full charge open terminal voltage = 13.26V
specific gravity = about 1285 (in all 6 cells)
i left disconnected battery for whole night and voltage after about 12 hours = 12.76V
when UPS is connected the terminal voltage remains 13.76 all the time and when battery is fully charged UPS gives about 3A current pulse periodically.
when battery is discharged UPS gives about 15A constant which then reduced to 7A so it seems it has 3 step charger.
What will be the cause of reduced backup? BTW battery is fully drained several times coz of loadsheding

[Xulfiqar]

you should put your battery on a rapid and slow charge cycle, a standing voltage of 12.76 volts and reduced ampacity is a sign of a mixture too strong. If you check when the battery starts gassing you will see that the SG is high.

[Xulfiqar]

I am having good experience with using only the battery water sold by the battery wala shop. not talking about the packed bottles. Just buy the open diluted water from any battery shop.

you do know that is acid right? keep adding acid and you will end up with a completely dead battery in short order.

[a_n_memon88]

you should put your battery on a rapid and slow charge cycle, a standing voltage of 12.76 volts and reduced ampacity is a sign of a mixture too strong. If you check when the battery starts gassing you will see that the SG is high.

What should be ideal static voltage to indicate proper mixture my UPS batteries show 12.57-12.6 volts

[Xulfiqar]

ideal voltage is 12.6 as the battery is made of 6 2.1 volt cells.

[a_n_memon88]

ideal voltage is 12.6 as the battery is made of 6 2.1 volt cells.

arent they 6 2 volt cells i.e 12 volts

[Xulfiqar]

arent they 6 2 volt cells i.e 12 volts

no they are 6 2.1 volt cells totalling 12.6 volts - generally known as 12V batteries, elec equipment on cars are meant to be run at 14V yet the car is stated to have a 12V system.

[umans]

you should put your battery on a rapid and slow charge cycle, a standing voltage of 12.76 volts and reduced ampacity is a sign of a mixture too strong. If you check when the battery starts gassing you will see that the SG is high.

i cant configure the UPS charging mechanism.it seems like micro controller based charger and it doesn't provide any interface to configure its parameters.reverse engineering will require hell of effort.
battery was overfilled 1st time when i added the electrolyte and now it is on upper level.i think as the water is evaporated thus concentration of electrolyte is increased.should i replace some electrolyte with distilled water?

[Xulfiqar]

i cant configure the UPS charging mechanism.it seems like micro controller based charger and it doesn't provide any interface to configure its parameters.reverse engineering will require hell of effort.
battery was overfilled 1st time when i added the electrolyte and now it is on upper level.i think as the water is evaporated thus concentration of electrolyte is increased.should i replace some electrolyte with distilled water?

find a good battery shop or mechanic who has a dedicated battery charger, charge at 10% of the battery stated AH and at gassing voltage, this will ensure all the electrolyte is mixed thoroughly, let it cool then check SG - adjust as required.

[umans]

find a good battery shop or mechanic who has a dedicated battery charger, charge at 10% of the battery stated AH and at gassing voltage, this will ensure all the electrolyte is mixed thoroughly, let it cool then check SG - adjust as required.

thanx bro...... u r absolutely right but its too heavy for me to lift and move from 1st floor to ground and its hard to find some reasonable battery shop who can do it for me.anyways! I'll try to replace some electrolyte with deionized water and see the difference....

[Xulfiqar]

thanx bro...... u r absolutely right but its too heavy for me to lift and move from 1st floor to ground and its hard to find some reasonable battery shop who can do it for me.anyways! I'll try to replace some electrolyte with deionized water and see the difference....

heavy - do you have some special condition?

[umans]

heavy - do you have some special condition?

well! its about 40kg and I'm avoiding hassle.....(working 16h a day these days:'( ) also i know the response of battery shop so i think i should better do it myself.....

[longdrive]

Microcontroller based inverters do not seem to completely stop charging when full, I can also measure about 13.7 volts at Homage Inverter terminals once its fan goes off. This seems to be float or trickle charge.
Can flooded batteries (like local AGS Exide etc) bear this float charge??? Or should they be disconnected once the Inverter completes its fast charge i.e. brings up the battery voltage to 13.7??